Among given species identify the isostructural pairs:

(1) $\left[N{F}_{3<mspace\; width="1em"></mspace>}<mspace\; width="1em"></mspace>and<mspace\; width="1em"></mspace>B{F}_3\right]$

(2) $\left[B{F_4}^{-}<mspace\; width="1em"></mspace>and<mspace\; width="1em"></mspace>N{H_4}^{+}\right]$

(3) $\left[BC{l}_3<mspace\; width="1em"></mspace>and<mspace\; width="1em"></mspace>BrC{l}_3\right]$

(4) $\left[N{H}_3<mspace\; width="1em"></mspace>and<mspace\; width="1em"></mspace>N{O_3}^{-}\right]$

In which of the following cases $\mathrm{C}—\mathrm{C}$ bond length will be highest?

(1) ${\mathrm{CH}}_3—{\mathrm{CF}}_3$                               (2) ${\mathrm{FCH}}_2—{\mathrm{CH}}_2\mathrm{F}$

(3) ${\mathrm{F}}_2\mathrm{CH}-{\mathrm{F}}_2\mathrm{CH}$                            (4) ${\mathrm{CF}}_3—{\mathrm{CF}}_3$

The ratio of $\mathrm{\sigma }<mspace\; width="1em"></mspace>/<mspace\; width="1em"></mspace>\mathrm{\pi }<mspace\; width="1em"></mspace>\mathrm{bond}<mspace\; width="1em"></mspace>$ in tetracyano ethylene is: 

(1) 2:1

(2) 1:1

(3) 1:2 

(4) none of these 

Which of the following statement is correct in the context of the allene molecules, $C_3{H}_4$?

1. The central carbon is Sp hybridized

2. The terminal carbon atoms are $s{p}^2$ hybridized

3. The planes containing the $C{H}_2$ groups are  mutually perpendicular to permit the formations of two separate $\pi$ - bonds 

4. All are correct 

The shape of $\mathrm{Xe}{{\mathrm{F}}_3}^{+}$ is:

Which of the following shape are not possible for possible value of 'n' in $XeFn$ molecule?

(1) Linear 

(2) Square planar 

(3) Trigonal planar

(4) Capped octahedral

Which of the following compound has a maximum "C$—$C" single bond length?

1. CH₂CHCCH        
2. HCCCCH  
3. CH₃CHCH₂        
4. CH₂CHCHCH₂

$BeC{l}_2$ is not isostructural with :

(1)$IC{l_2}^{-}$

(2) $C_2{H}_2$

(3) $Xe{F}_2$

(4) $GeC{l}_2$

Minimum $\mathrm{F}—\mathrm{S}—\mathrm{F}$ bond angle present in:

1. ${\mathrm{SSF}}_{2<mspace\; width="1em"></mspace>}$                                                     

2. ${\mathrm{SF}}_6$

3. ${\mathrm{SF}}_2$                                                       

4. ${\mathrm{F}}_3\mathrm{SSF}$

$Sb{F}_5$ reacts with $Xe{F}_4$ and $Xe{F}_6$ to form ionic compounds $\left[Xe{F_3}^{+}\right]$ $\left[Sb{F_6}^{-}\right]$ and $\left[Xe{F_5}^{+}\right]$ $\left[Sb{F_6}^{-}\right]$ then molecular shape of $\left[Xe{F_3}^{+}\right]$ ion and $\left[Xe{F_5}^{+}\right]$ ion respectively :

(1) Square pyramidal, T-shaped 

(2) Bent T-shape, Square pyramidal

(3) See- saw , square pyramidal 

(4) Square pyramidal , See-saw